The present invention relates to communication cables and more particularly to the flat multi-conductor type suitable for laying under carpets or the like.
Stimulated by the growth of office automation with word and data processors, computors and the concept of centralized equipment serving a plurality of operators situated at separate stations, the need has developed for means capable of interconnecting a wide range of electronic equipment located at disparate points throughout an office space or facility. Flat communication cables have been developed for this purpose which cables can be laid tape-like under carpeting or other floor covering to crisscross a room interconnecting peripheral and central equipment. Available flat cables, however, are costly and have limited versatility for handling diverse communication handling requirements.
Communication cables have various functions. They carry low voltage control currents from point to point and they carry signal currents. Some of the signals require a high degree of shielding to avoid unwanted signal pollution, others do not. With classical round wire cabling an equipment manufacturer would specify the type wire and gauge, whether it is to be shielded or not, coaxial or parallel or twisted, and the cable manufacturer merely selected and bundled the appropriate elements. It is not believed that methods were known heretofore for producing flat cables with the same diversity.
It, therefore, is an object of the present invention to provide a flat communication cable that can be made with conventional equipment using low cost tooling and relatively low cost materials. The new cable construction provides considerable versatility in the selection of shielding methods both between pairs and between adjacent cables and, thus, provides control over cable characteristics such as capacitance and crosstalk.